Power-actuated distributing conveyor system for a ready-mix concrete truck

ABSTRACT

A distributing conveyor system embodying a pivot arm hingedly connected to the rear end of a ready-mix concrete truck, a rotary carrier frame on the distal end of the pivot arm, and a belt-type conveyor including a boom which is slidable endwise through the carrier frame, together with hydraulically powered means for swinging the pivot arm toward and away from the truck, and for rotating the carrier frame.

United States Patent [191 Spellman Aug. 13, 1974 POWER-ACTUATED DISTRIBUTING CONVEYOR SYSTEM FOR A READY-MIX CONCRETE TRUCK Francis T. Spellman, Blue Springs, Mo.

Symons Corporation, Des Plaines, Ill.

Inventor:

Assignee:

Filed:

Appl. No.:

May 23, 1973 US. Cl. 214/8326, 259/169 Int. Cl. B60p l/36,' 828C 7/ 16 Field of Search 214/8326, 520, 521, 522;

References Cited UNITED STATES PATENTS 3,347,350 10/1967 Lindstromet a1. 214/521 X 1 1 m r-urn 12 64 Duecy 259/169 Spellman 259/169 Primary Examiner-Robert J. Spar Assistant Examiner-Les1ie J. Papemer Attorney, Agent, or Firm-Norman H. Gerlach 57 ABSTRACT A distributing conveyor system embodying a pivot arm hingedly connected to the rear end of a ready-mix concrete truck, a rotary carrier frame on the distal end of the pivot arm, and a belt-type conveyor including a boom which is slidable endwise through the carrier frame, together with hydraulically powered means for swinging the pivot arm toward and away from the truck, and for rotating the carrier frame.

20 Claims, 6 Drawing Figures PATENIEDAUSI 1 14 3,828,949

SHEET 1 0F 3 Pmmanwm 3.828.949

SHEET 3 OF 3 FIG.4

POWER-ACTUATED DISTRIBUTING CONVEYOR SYSTEM FOR A READY-MIX CONCRETE TRUCK The present invention relates generally to a vehicle mounted concrete distributing conveyor system which is primarily designed for use in connection with a vehicle of the general type which is commonly referred to as a ready-mix concrete truck, such a vehicle consisting of a wheeled automotive truck chassis on which there is mounted a rotary concrete mixing drum by means of which concrete-mixing operations may be carried out while the vehicle is in transit to a scene of concretepouring operations and from which drum the concrete is progressively withdrawn and directed through a downchute for subsequent concrete placement purposes. The invention is particularly concerned with a concrete distributing conveyor system of the type which is shown and described in applicants copending U.S. Pat. application Ser. No. 208,682, filed on Dec. 16, 1971, and entitled DISTRIBUTING CONVEYOR SYSTEM FOR A ROTARY CONCRETE MIXING OR OTHER TRUCK, now U.S. Pat. No. 3,768,784, and the primary object of the present invention is to provide a distributing conveyor system which is an improvement on, and embodies certain inherent advantages over, that of said patent application.

Briefly, the conveyor system of the aforementioned copending patent application is associated with and also mounted upon a so-called ready-mix truck and it consists essentially of four principal relatively movable components, namely, a pendulum bracket which is hinged for limited swinging movement about a horizontal axis and in a plane which extends transversely of the truck chassis, and is mounted for such swinging movement on a rear transverse chassis frame member, a pivot arm which is hinged to the pendulum bracket for swinging movement about a substantially vertical axis and in a substantially horizontal plane between a folded position wherein it lies close to the pendulum bracket and an extended position which may lie at any angle within a 180 swing of the pivot arm, a carrier frame which is both tiltably and rotationally mounted on the outer free end of the pivot arm, and a conveyor boom which is slidable endwise through the carrier frame. By swinging the pivot arm to an extended position, positioning the carrier frame at a desired angle, and shifting the conveyor boom endwise for any desired degree of projection on either side of the carrier frame, a wide variety of concrete placements is made possible. Both high and low, short or long pours within a relatively long radius and within a relatively wide arcuate swing, well in excess of 180, are available by selective placement or positioning of these four conveyor components.

Structurally, the conveyor system of the present invention is similar to that of the aforementioned copending patent application in which it embodies the same four principal components in substantially the same form and in precisely the same articulated relationship. However, whereas in the conveyor system of said patent application hydraulic means are provided for actuating only the pendulum bracket for conveyorlevelling purposes, and for tilting the carrier frame for the conveyor boom so as to effect different pouring heights, in the present conveyor system all phases of conveyor component movement are hydraulically controlled and power-actuated.

In the conveyor system of the aforesaid patent appli cation, swinging movement of the pivot arm away from the vehicle chassis is manually accomplished and this sometimes taxes the strength of the operator. Additionally, rotation of the conveyor boom-supporting carrier frame is accomplished manually, the arduousness of this task being dependent upon the augularity of the carrier frame at the time such rotation is undertaken. This is particularly true when the conveyor boom is loaded with concrete mix.

The present invention represents an improvement over the conveyor system of the aforementioned application in that novel power swing means is provided for power-actuating the pivot arm so as to swing it away from its parked or inoperative position against the truck chassis and effect a desired placement thereof, while additional novel power swing means is provided for rotating the carrier frame which supports the conveyor boom.

Insofar as the means for power-actuating the pivot arm is concerned, this means takes the form of an hydraulic cylinder and plunger arrangement, together with a folding four-bar linkage system which, when the pivot arm is in its folded parked position, itself assumes a folded position close to the vehicle frame. This linkage system is possessed of a magnification factor whereby a relatively large swing of the pivot arm may be accomplished with a relatively short hydraulic cylinder, the cylinder and its linkage system consuming very little space when the various parts are in their folded parked positions.

Insofar as the means for power-actuating the carrier frame is concerned, this means assumes the form of a rotary hydraulic motor which is mounted directly on the pivot arm and is effectively connected to the carrier frame by a chain and sprocket arrangement which while possessing a large gear reduction factor consumes but very little space and in no way interferes with full movement of other components of the conveyor system.

The provision of novel power swing means for actuating both the pivot arm and the carrier frame components of a conveyor system of the general type shown and described in aforementioned copending application Ser. No. 208,682 outlined above and possessing the stated advantages, constitutes the principal object of the present invention.

Numerous other objects and advantages of the invention, not at this time enumerated, will readily suggest themselves as the nature of the invention is better understood from a consideration of the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly defined by the claims at the conclusion hereof.

In the accompanying three sheets of drawings forming a part of this application, one illustrative embodiment of the invention is shown.

In these drawings:

FIG. 1 is a fragmentary rear perspective view of a concrete mixing truck, such view showing the poweractuated articulated concrete operatively installed on the rear end of the truck;

FIG. 2 is an enlarged fragmentary perspective view of the proximate end region of the conveyor-supporting pivot arm assembly which is employed in connection with the invention, such view showing the hydraulic power drive for such pivot arm;

FIG. 3 is a fragmentary top plan view of a portion of the structure of FIG. 2;

FIG. 4 is a fragmentary perspective view of the distal end of the conveyor-supporting pivot arm assembly, such view showing the hydraulic power drive for the conveyor frame of the system;

FIG. 5 is an enlarged exploded perspective view of a connector link which is employed in connection with the invention, together with its associated fastening devices; and

FIG. 6 is a reduced rear exploded perspective view of the structure of FIG. 4, the view encompassing certain sprocket-mounting features not embodied in FIG. 4.

Referring now to the drawings in detail and in particular to FIG. 1, a concrete mixing and distributing truck is designated in its entirety by the reference numeral 10, only the rear end portion of such truck being shown. A truck of the character with which the present invention is concerned is commonly known and referred to in the industry as a ready-mix truck and, as a consequence, such designation will be employed throughout this specification and in the appended claims. The truck 10 is provided with concrete mixing and distributing facilities of the general type shown and described in aforementioned U.S. Pat. application Ser. No. 208,682, only such facilities as bear a direct relationship to the present invention being illustrated herein. For a full understanding of the concrete mixing and distributing system with which the present invention is associated, reference may be had to such application which, by reference thereto, is hereby incorporated in and made a part of the present application insofar as it is consistent with the present disclosure.

Insofar as the fragmentary disclosure of FIG. 1 is concerned, the truck chassis 12 is supported by powerdriven rear wheels 14. It is to be understood that the chassis 12 serves to support the usualrotary concretemixing drum, an operators cab, a downchute from which concrete issuing from the drum is delivered to the improved distributing conveyor system, and numerous other components, instrumentalities and devices which have not been disclosed herein but the nature and function of which may be ascertained by reference to aforementioned patent application Ser. No. 208,682. Included in the present disclosure, however, is the rear drum support 16 which projects upwardly from the chassis l2 and, in combination with a similar front drum support (not shown), serves to support the rotatable drum. Also included in the disclosure are the left truck fender 18, the right truck fender 19 which receives the conveyor boom thereon when the latter is in a parked or inoperative position, and the downchute supporting arm 20.

The concrete distributing conveyor system of the present disclosure is substantially the same as that shown in U.S. Pat. application Ser. No. 208,682 and it includes a conveyor boom 22 which is slidable lengthwise in and through a tiltable traverse carrier frame 24, the latter being mounted for fore-and-aft tilting movement on a turntable 26 which is capable of rotational movement about a substantially vertical axis on the distal or outer end of a support bracket or pivot arm 28. The proximate or inner end of the pivot arm 28 is pivotally connected to a conveyor-levelling pendulum bracket 30 which, in turn, is pivotally connected to a mounting plate 31, the latter being welded or otherwise secured to the chassis 12. The pendulum bracket 30 is thus mounted for limited swinging movement about a horizontal axis. The purpose of the swinging pendulum bracket is to effect levelling of the conveyor boom 22 in a manner and for a purpose that will be made clear presently.

The aforementioned basic components of the concrete distributing conveyor system, namely, the conveyor boom 22, the traverse carrier frame 24, the turntable 26, the pivot arm 28 and the pendulum bracket 30 have not been fully illustrated herein but they appear inconsiderable detail in aforesaid U.S. Pat. application Ser. No. 208,682 to which reference may be had for a full understanding of both their structure and function. It is deemed sufficient for purposes of discussion herein to state that the net result of the various movements of which these components are capable is, in various combinations of movements, to establish an infinite and universal movement of the conveyor boom 22 with respect to the truck chassis 12 for concrete placement purposes.

The support bracket or pivot arm 28 for the turntable 26 is in the form of a generally trapezoidal frame structure and includes an inner or proximate vertically extending end piece 32, an outer or distal vertically extending end piece 34, an upper frame piece 36 between the upper ends of the end pieces 32 and 34, and a lower frame piece 38 between the lower ends of said end pieces. The inner end piece 32 is in the form of a vertically extending sleeve which is rotatably carried on a generally vertically extending fixed supporting or hinge shaft 40 (see FIGS. 1 and 2). This hinge shaft 40 is rotatably supported at its upper and lower ends by laterally extending ears 42 and 44 which project rearwardly from the pendulum bracket 30. As best shown in FIG. 2, the upper region of the pendulum bracket 30 is pivotally connected by a horizontally extending bolt 46 for limited swinging movement on the aforementioned mounting plate 31 throughout a small angle under the control of an hydraulic device in the form of a plunger 50 the outer end of which is pivoted to the lower end of the pendulum bracket 30, and a levelling cylinder 52 the closed end of which is pivoted to a depending bracket 54 on the chassis 12.

As heretofore indicated, the traverse carrier frame 24 is tiltable bodily, together with the conveyor boom 22 which is slidably carried thereby, for rocking movements about a horizontal axis in a fore-and aft direction. Accordingly, the pivotal connection for the carrier frame is established by means of a traverse U-frame 60 having a pair of upstanding side arms 62 and a connecting base portion 64 (see particularly FIG. 4). The U-frame 60 is welded or otherwise fixedly secured to the turntable 26 so that it turns bodily therewith. The vertical or upstanding side arms 62 of the U-frame straddle the traverse carrier frame 24 and the upper regions of these arms are provided with inwardly extending trunnions, one of which appears at 66 in FIG. 1 of the drawings, these trunnions constituting the pivotal connection for the carrier frame 24 and the conveyor boom 22 which is carried thereby.

A pivot shaft 70 depends centrally from the turntable 26 and is rotatable in the outer or distal end piece 34 of the pivot arm 28, said end piece being in the form of a tubular sleeve which encompasses the shaft 70. The pivot shaft 70 constitutes the main reaction memher for the entire concrete distributing conveyor system, the shaftbeing capable of limited tilting movement in a plane which extends vertically and transversely with respect to the truck chassis 12, such tilting movement being incident to a correspondingrocking or swinging movement of the pendulum bracket 30.

The details of the conveyor boom 22 and also the traverse carrier frame 24 which supports the boom and through which the latter is slidable have not been disclosed herein since they are identical with the boom and carrier frame of aforementioned copending application Ser. No. 208,682. However, it can be ascertained from FIG. 1 that the conveyor boom is guided in its endwise sliding movement through the carrier frame by means of lower supporting rollers 72 and upper hold-down rollers 74. Such rollers are mounted at the opposite ends of the traverse carrier frame 24 and are arranged in pairs with the rollers of each pair straddling one of a pair of horizontally extending channel members 76 which are substantially coextensive with the conveyor boom 22.

In order to effect tilting movements of the carrier frame 24 and the conveyor boom which is carried thereby, the lower end of the pivot shaft 70 projects below the sleeve-like end piece 34 of the .pivot arm 28 as shown in FIGS. 1 and 4 and carries a split clamping collar 80 to which there is pivoted the outer end of a plunger 82, the latter being associated with an upwardly and outwardly inclined lift cylinder 84. The closed lower end of the lift cylinder is pivotally connected to the carrier frame 24 at a point remote from the trunnions 66.

It is to be understood that the conveyor boom 22 which slides endwise through the carrier frame 24 as previously described has associated therewith an endless conveyor belt which is substantially coextensive with the boom and is supported by the usual head and tail pulleys near the opposite ends of the boom, the head pulley being motor-driven. This belt and its associated pulleys do not appear herein due to the retracted position of the conveyor boom. However, for a full disclosure of such conveyor belt and pulleys, reference may be had to aforementioned copending US. Pat. application Ser. No. 208,682. The forward end of the boom 22 is provided with the usual discharge hood 86 while a concrete-receiving hopper 88 which is supported on the carrier frame 24 receives concrete in stream form from a concrete placement chute, the latter being in communication with the discharge opening of the rotary concrete mixing drum on the truck chassis 12.

The arrangement of parts thus far described, and particularly the disposition of the articulated conveyor distributing system including the pendulum bracket 30, the pivot arm 28, the turntable 26, the tiltable carrier frame 24 and the actuating cylinders 52 and 84 for the pendulum bracket 30 and carrier frame 24, respectively, are substantially the same as those associated with the conveyor distributing system of aforementioned copending application Ser. No. 208,682 and no claim is made herein to any novelty associated with the same, the novelty of the present invention residing rather in the provision of hydraulic means for swinging the pivot arm 28 about the substantially vertical axis of the hinge shaft 40, and the provision of hydraulic means for effecting rotary movements of the turntable 26 for angular conveyor boom placement purposes as will now be fully described and subsequently claimed.

Whereas, in the conveyor system of the aforementioned copending patent application, the angular positioning of the pivot arm 28 is effected manually and, hence, taxes the strength of even two operators, the present invention affords a means whereby this pivot arm may be power swung to any selected angular position. To accomplish this, the earlier cogwheel and dog arrangement at the inner or proximate end of the pivot arm has been eliminated so that an infinite adjustment of the angular position of the pivot arm may take place under the control of an hydraulic linkage system which is powered by an hydraulic pivot arm cylinder as will be described presently. Additionally, whereas in the earlier conveyor system, the angular positioning of the conveyor boom 22 also is manually effected and the adjusted position of such boom is maintained by a similar cogwheel and dog arrangement, the present invention eliminates such an arrangement and, in its stead, there is provided a chain and sprocket drive for the turntable 26, such drive being powered by a rotary reversible hydraulic turntable motor 102 as also will be described in detail subsequently.

Considering first the power swing arrangement for the pivot arm or support bracket 28, and referring particularly to FIGS. 2 and 3 of the drawings, the aforementioned hydraulic pivot arm cylinder 100 (see FIG. 1) has its closed end pivotally connected by a yoke and bracket structure 104 to the truck chassis 12. Said cyl- I inder 100 has associated therewith a plunger 106 the outer end of which is pivotally connected to the medial region of a hinged, horizontally extending connector link 108, the details of which are illustrated in FIG. 5. The inner or proximate end of the connector link 108 is pivoted to a U-shaped bracket 110 which is welded or otherwise affixed to the truck chassis 12, while the outer or distal end of the link 108 is pivotally connected to one endof an adjustable length tie bar 112. The other end of the tie bar 112 is pivotally connected to the medial region of the upper frame piece 36 of the pivot arm 28 by means of a bracket and post arrangement 114 the nature of which will be set forth presently.

The nature of the connector link 108 is best illustrated in FIG. 5 of the drawings. This link is formed of two flat strips of metal stock and comprises an upper strip and a lower strip 122, the two strips being maintained in spaced apart relationship by means of an angular web 124. The latter has web sections 126 which extend diagonally across the upper and lower strips 120 and 122, and a medial web section 128 which extends between adjacent edges of the strips. The proximate ends of the strips 120 and 122 are provided with vertically aligned holes 130 which receive therein the opposite ends of a vertically extending, combined bushing and pivot post 132, the latter being designed for reception therethrough of the shank portion of a vertically extending bolt 134. A nut 136 which is received on the lower end of the bolt shank portion beneath the lower strip 122 serves to maintain the pivot post 132 in position. A horizontally extending pivot ear 138 projects laterally from the medial web section 128 of the angular web 124 midway between the two strips 120 and 122 and has formed therein a hole 140 which is in vertical alignment with a hole 142 in the upper strip 120. A yoke 144 is carried at the outer end of the plunger 106 (see FIG. 2) and straddles the pivot ear 138, while the shank portion of a vertically extending bolt 146 passes through the holes 140 and 142, as well as through the yoke 144 and establishes the pivotal connection between the medial region of the connector link 108 and the distal end of the plunger 106. Aligned holes 150 are formed in the upper and lower strips 120 and 122 near the proximate end of the connector link 108 and are designed for registry with a pair of aligned holes 152 in the U-shaped bracket 110, the four holes 150, 152 receiving therethrough a vertically extending bolt 154 which establishes the pivotal connection whereby the proximate end of the connector link 108 is secured to the truck chassis 12.

The horizontally extending tie bar 112 which effectively extends between the outer or distal end of the connector link 108 and the upper frame piece 36 of the pivot arm 28 is of two-piece construction and consists of an elongated, internally threaded, tubular section 156 and an externally threaded, rod-like section 158, the latter being telescopically and threadedly received within the section 158 so that by rotating the section 158 in opposite directions, the effective length of the time bar 112 may be varied as desired. The outer end of the section 156 of the tie bar 112 carries a bearing sleeve 160 which is received over the aforementioned pivot post 132 while the section 158 carries at its outer end a similar bearing sleeve 162. The latter is received over a vertically extending bearing post 164 which is welded to the upper surface of a bracket 166, such bracket being secured by bolts 168 to the upper frame piece 36 of the pivot arm 28. A bolt 170 passes upwardly through the bracket 166 and the bearing post- 164 and receives thereon a nut 172 by means of which the bearing sleeve 162 is captured on the post 164. More specifically, the bracket 166 embodies a saddle portion 174 which seats on the upper frame piece 36 and is bolted thereto by the aforementioned bolts 168, and, in addition, a laterally offset raised shelf portion 176 on which the bearing post 164 is mounted and through which the bolt 170 passes.

From the above description, it will be apparent that when hydraulic fluid is supplied to the cylinder 100 in such a manner as to project the plunger 106, the hinged connector link 108 will be swung in a clockwise direction as viewed in FIG. 3, thus placing the tie bar 112 under compression and causing the pivot arm 28 likewise to swing in a clockwise direction. Retraction of the plunger 106 will place the tie bar 112 under tension and effect swinging of the pivot arm 28 in a counterclockwise direction.

It is here pointed out that, in the parked or inoperative condition of the component parts of the conveyor system, the pivot arm 28 lies close to the rear end of the truck chassis 12 and extends transversely of the same. In this condition of the parts, the hydraulic cylinder 100, the hinged connector link 108, the tie bar 112 and the pivot arm 28 are closely nested together and lie close to the rear end of the truck chassis 12. The connector link 108 and the cylinder 100 are disposed at substantially the same horizontal level and as the parts move into their closely nested position, the connector link actually engages the cylinder 100 and, in order that a more closely nested relationship may take place, relief notches 180 (see FIGS. 2 and 3) are formed in the upper and lower strips 120 and 122 of the connector link 108, these notches mating with and straddling the adjacent circular rim region of the cylinder at such time as the connector link 108 moves into close proximity to the rearmost transverse member of the truck chassis 12. The nesting of the parts is, however, such that there is neither an over-center or a dead-center position so that when fluid under pressure is supplied to the cylinder to project the plunger 106, the aforementioned linkage arrangement will function to swing the pivot arm 28 outwardly away from the chassis 12.

It is to be noted with reference to FIG. 3 that the linkage arrangement which includes the tie bar 112, the connector link 108, a limited proximate portion of the pivot arm 28, and a limited portion of the truck chassis 12 constitutes, in effect, an articulated four-bar linkage wherein the limited portion of the chassis constitutes a fixed bar, the connector link 108 and the limited portion of the pivot arm 28 constitute swinging bars, and the tie bar 112 constitutes a floating bar. This four-bar linkage is substantially completely collapsible which is to say that it may be folded so that all of the bars thereof extend in the transverse direction of the truck chassis. Since the outer end of the plunger 106 is connected to the swinging bar, i.e., the connector link 108, this latter bar constitutes the driving bar for motivation of the four-bar linkage.

Considering now the manner in which rotational movement is applied to the turntable 26 for conveyor boom placement or positioning purposes, and referring to FIGS. 1, 4 and 6 ofthe drawings, the turntable is comprised of three principal parts, namely, a circular bottom plate 200 (see FIG. 6) which has a toothed periphery and functions as a driven sprocket, a cylindrical side wall 202, and a circular top plate 204. Fastening screws, one of which is indicated by the reference numeral 206, project upwardly through the bottom plate 200 and also spacer sleeves 208 and are received in tapped holes 210 in the top plate 204. The latter is welded or otherwise fixedly secured to the underneath side of the base portion 64 of the traverse U-frame 60.

The turntable bottom plate 200 (which hereinafter will be referred to as a sprocket) is connected by an endless chain 212 to a dual sprocket assembly 214 (see FIGS. 4 and 6) which is rotatably mounted on a bearing post 216. The latter projects upwardly from a saddle member 218 which is seated on the upper frame piece 36 of the pivot arm 28 and is secured thereto by bolts 220. The sprocket assembly 214 includes a small diameter sprocket 222 and a large diameter sprocket 224, the chain 212 passing around the small sprocket 222. The large diameter sprocket 224 is connected by an endless chain 226 (see FIG. 4) to a small diameter driving sprocket 228 which is mounted on the upper end of the output shaft 230 of the aforementioned hydraulic motor 102.

The reversible hydraulic motor 102 is fixedly secured to the upper frame piece 36 of the pivot arm 28 by means of a motor mount or bracket 232 which is secured by welding to both the upper frame piece 36 and the casing of the hydraulic motor 102. A rubber or other elastomeric cover guard 234 of dome shape configuration overlies the entire chain and sprocket drive mechanism and is secured by nut and bolt assemblies 236 to the underneath side of the connecting base portion 64 of the traverse U-frame 60.

From the above description, it will be apparent that when the hydraulic motor 102 is supplied with fluid under pressure for rotation of the motor shaft 230 and small sprocket 228 in either direction, a relatively large gear ratio reduction drive will be effected to the end that the large sprocket 200, the turntable 26 and the traverse U-frame60 will be rotated about the axis of the pivot shaft 70 in one direction or the other, as the case may be, thus swinging the entire conveyor assembly including the conveyor boom 22 about such axis. It will be understood, of course, that such actuation of the hydraulic motor 102 and consequent swinging of the conveyor boom 22 may be initiated regardless of the angular disposition of the latter as controlled by the lift cylinder 84 and regardless of the direction or magnitude of extent of the conveyor boom.

It will be understood that the various positions of which the pendulum bracket 30, the pivot arm 28, the traverse U-frame 60, and the conveyor boom 22 are capable of assuming are substantially the same as those which are capable of being assumed by the corresponding components of the conveyor system of aforementioned copending U.S. Pat. application, Ser. No. 208,682. Thus, and as may be more clearly visualized by reference to the specification and drawings of such application, when the components of the present conveyor system are in their parked or inoperative positions, the pivot arm 28 lies substantially flush against the rearmost transverse member of the truck chassis 12 while the upper frame piece 36 of the pivot arm 28 rests upon and lies within the confines of a hook-like bracket 240 which is secured to such rearmost transverse frame member. At the same time, the conveyor boom 22 is fully extended from the traverse U-frame 60 in an extreme position which causes it to overlie and rest upon the right-hand fender of the truck.

In the operation of the herein described power swing mechanism, assuming that the components of the conveyor system are in their parked condition as set forth above, and further assuming that any safety lock mechanism such as strapping material or the like which may be employed for holding the conveyor boom 22 on the fender 19 has been removed, hydraulic pressure fluid will initially be applied to the levelling cylinder 52, thus retracting the plunger 50 thereof and swinging the pendulum bracket 30 in counterclockwise direction as viewed in both FIGS. 1 and 2 throughout'a small angle. This slight shifting movement of the pendulum bracket 30 raises the pivot arm 28 sufficiently that the upper frame piece 36 thereof clears the hook-like bracket 240 on the rear transverse member of the truck chassis 12 and, additionally, it lifts the conveyor boom 22 from its position of rest on the rear right fender 19 of the truck and to such a height that it clears any retaining flanges or the like which may be provided on the fender for preventing dislodgment of the conveyor boom during travel of the truck from one place to another. Thus, after the pendulum bracket 30 has thus been shifted, both the pivot arm 28 and the conveyor boom 22 are free of the truck chassis so that they may be swung to selected operative concrete pouring or distributing positions.

With the pivot arm 28 and the conveyor boom 22 thus released from the truck chassis, hydraulic pressure fluid may be selectively applied to the various hydraulic cylinders 52, 84, 100, as well as to the hydraulic motor 102, for conveyor boom placement purposes. Ordinarily, fluid under pressure will first be applied to the cylinder 100 so that, upon projection of the associated plunger 106, the connector link 108 will be swung outwardly and away from the rear transverse member of I the chassis l2, and also away from its nested position in close proximity to the cylinder 100. This swinging movement of the connector link 108 will, as previously described, place the tie bar 112 under compression, and thus, swing the pivot arm 28 away from the chassis 12 to any desired or selected position. It is to be particularly noted at this point that the four-bar linkage system which includes the plunger 106, the connector link 108, the tie bar 112, and the pivot arm 28 is possessed of a magnification factor wherein a very small movement of the plunger 106 will result in a comparatively large angular swinging movement of the pivot arm 36. By such an arrangement, a relatively short cylinder may be, employed.

After the pivot arm 28 has thus been brought to a selected position, as, for example, the position in which it is shown in FIG. 1, hydraulic pressure fluid will be supplied to the rotary hydraulic cylinder 102 in a direction which will effect rotary motion of the traverse U- frame 60 to bring the conveyor boom 22 to the desired angular position with respect to the longitudinal direction of the truck chassis. This rotary motion of the U- frame may be preceded by an endwise adjustment of the position of the conveyor boom or such adjustment of the boom may follow the positioning of the traverse U-frame 60. It will be understood, of course, that where different pouring installations are concerned, the particular sequence of operation of the various hydraulic control cylinders and of the hydraulic motor 102 will vary according to the dictates of the operator or operators. In all situations, however, it will be necessary, in order to dislodge the conveyor boom 22 from its parked position on the right fender 19 by initially operating the hydraulic cylinder 52 as previously described in order to rock the pendulum bracket 30 and cause lifting of the distal end of the pivot arm 28 so as to free the pivot arm from its hook-like retention bracket 240, and then immediately to actuate the cylinder 100 in order to swing the pivot arm 28 away from the rear end of the chassis 12. After this has been done, the turntable 26, the traverse U-frame 60, and the other conveyor structure and instrumentalities which are supported at the distal end of the pivot arm will be removed from the truck chassis a sufficient distance that there will be clearance room for freedom of movement of the boom 22 in whatever direction is considered appropriate.

It will be also understood that the various hydraulic control devices including the cylinders 52, 100 and 84, and also the hydraulic motor 102, will be supplied with hydraulic pressure fluid under the control of an appropriate hydraulic control system including a powerdriven fluid pump which will be operatively installed upon the truck chassis 12, together with a suitable control valve or bank of such valves which will be readily accessible to the operator of the truck. Ordinarily, there will be a single control valve for each hydraulic component, although such valves may be embodied in a single valve casing if desired.

Finally, it will be apparent that the particular manipulation of the various control valves to accommodate any given concrete pour need not necessarily be a sequential manipulation. An experienced operator may, if desired, effect simultaneous manipulation of the control valves to bring the conveyor boom 22 to its final pouring position. For example, if, after release of the conveyor boom 22 and the pivot arm 28 from their parked positions, an operator ascertains that in the final position of the conveyor boom 22 a short pour operation is required wherein the conveyor boom will ultimately be disposed so that it assumes a mid-position in the traverse carrier frame 24, the control valves by means of which endwise movement of the conveyor boom 22 is effected may be manipulated simultaneously with the manipulation of the control valve which actuates the cylinder 100. In this manner, endwise shifting of the conveyor boom 30 may take place during the swinging movement of the pivot arm 28 to its final position. Similarly, the hydraulic motor 102 may be actuated during swinging movement of the pivot arm 28so that when the latter arm reaches its final position of adjustment, the conveyor boom will assume a nearly correct position which can then be perfected by further actuation of the appropriate control valve or valves. As is the case in connection with the concrete distributing conveyor system of aforementioned copending US. Pat. application Ser. No. 208,862, the hydraulic levelling cylinder 52 is employed not only for initially rocking the pendulum bracket 30 so as to elevate the conveyor boom 22 and the pivot arm 28 in order to release the same from their parked positions, but also for side-to-side levelling of the conveyor boom, and consequently, the conveyor belt which is associated therewith for proper functioning of such belt during concrete-pouring operations.

The hydraulic control system by means of which the various disclosed hydraulic components 52, 100, 84 and 102 are actuated has not been disclosed herein since such system, per se, is not considered to be a part of the present invention. The control system whereby hydraulic components which are functionally equivalent to the hydraulic cylinders 52 and 84 is fully disclosed in aforementioned US. Pat. application Ser. No. 208,682 and it will be understood that control of the hydraulic cylinder 100 and the reversible hydraulic motor 102 will be effected by additional and appropriate solenoid-actuated control valves which may be incorporated in the fender-mounted control panel of the conveyor system of such patent application.

The invention is not to be limited to the exact arrangement of parts shown in the accompanying drawings or described in this specification as various changes in the details of construction may be resorted to without departing from the spirit or scope of the in vention. Therefore, only insofar as the invention is particularly pointed out in the accompanying claims is the same to be limited.

Having thus described the invention what I claim as new and desire to secure by letters patent is:

1. In a ready-mix concrete-transporting vehicle, in combination, a vehicle chassis having a rear transverse frame member, a normally vertical conveyor-levelling pendulum bracket pivotally mounted on the rear end of said frame member for limited angular displacement about a horizontally and longitudinally extending axis, a pivot arm having its proximate end hingedly secured to said pendulum bracket for swinging movement about a vertical axis, a turntable mounted on the distal end of said pivot arm for rotation about a vertical axis, a carrier frame pivotally mounted on the turntable for rotation bodily therewith and for fore-and-aft rocking movement about a horizontal axis, a conveyor boom slidable endwise in opposite directions through said carrier frame between projected positions on either side of the latter, an hydraulic lift cylinder operatively connected to the carrier frame and turntable for effecting rocking movements of the former, a levelling cylinder operatively connected to said frame member and pendulum bracket for effecting limited angular displacement of the latter, a tie bar pivotally connected at one end to said pivot arm, a connector link pivotally connected at one end to said frame member and at its other end to the other end of the tie bar, said tie bar and connector link, together with adjacent portions of the frame member and pivot arm, constituting an articulated collapsible four-bar linkage, and an hydraulic pivot arm cylinder operatively connected to said frame member and one bar of said four-bar linkage and effective to extend and collapse the latter.

2. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 1 and wherein the hydraulic cylinder is operatively connected to the connector link.

3. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 2 and wherein the pivot arm is capable of swinging movement from a retracted position wherein it extends transversely of the vehicle chassis and lies in close proximity to said transverse frame member, throughout an angle of substantially the tie bar is effectively connected to the pivot arm at a point close to the proximate end of the latter, and the pivot arm cylinder is connected to the connector link at a point close to the proximate end of such link.

4. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 3 and wherein the fourbar linkage is substantially completely collapsible so that when the pivot arm is in its retracted position, the tie bar, connector link, pivot arm and pivot arm cylinder assume a closely nested linear relationship in proximity to said transverse frame member.

5. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 4 and wherein the tie bar is extensible and contractible.

6. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 4 and wherein the tie bar comprises cooperating elongated internally and externally threaded members.

7. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 4 and including, additionally, a reversible hydraulic motor fixedly mounted on said pivot arm, and a power train operatively connecting said motor to the turntable in driving relationship.

8. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 7 and wherein the power train comprises a chain and sprocket mechanism.

9. In a readymix concrete-transporting vehicle, the combination set forth in claim 8 and wherein the hydraulic motor is mounted on the pivot arm in close proximity to the distal end of the latter.

10. In a ready-mix concrete-transporting vehicle, in combination, a vehicle chassis having a rear transverse frame member, a normally vertical conveyor-levelling pendulum bracket pivotally mounted on the rear end of said frame member for limited angular displacement about a horizontally and longitudinally extending axis, a pivot arm having its proximate end hingedly secured to said pendulum bracket for swinging movement about a vertical axis, a turntable mounted on the distal end of said pivot arm for rotation about a vertical axis, a carrier frame pivotally mounted on the turntable for rotation bodily therewith and for fore-and-aft rocking movement about a horizontal axis, a conveyor boom slidable endwise in opposite directions through said carrier frame between projected positions on either side of the latter, an hydraulic lift cylinder operatively connected to the carrier frame and turntable for effecting rocking movements of the former, a levelling cylinder operatively connected to said frame member and pendulum bracket for effecting limited angular displacement of the latter, a reversible hydraulic motor fixedly mounted on the pivot arm, and a power train operatively connecting said motor to the turntable in driving relationship.

11. In a ready-mix concrete-transporting vehicle, the combination set forth in claim and wherein the power train comprises a chain and sprocket mechanism.

12. In a ready-mix concretetransporting vehicle, the combination set forth in claim 10 and wherein the power train comprises an output driving sprocket on the hydraulic motor, a dual sprocket assembly mounted for rotation on the pivot arm, a driven sprocket on the turntable, a first endless chain operatively connecting said driving sprocket to a sprocket on the dual sprocket assembly, and a second endless chain operatively connecting the other sprocket on the dual sprocket assembly to the driven sprocket.

13. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 12 and wherein the hydraulic motor and its associated driving sprocket are mounted on the pivot arm in close proximity to the distal end of the latter.

14. In a ready-mix concrete-transporting vehicle, in combination, a vehicle chassis having a rear transverse frame member, a normally vertical conveyor-levelling pendulum bracket pivotally mounted on the rear end of said frame member for limited angular displacement about a horizontal longitudinal axis, a pivot arm having its proximate end hingedly secured to said pendulum bracket for swinging movement about a vertical axis, a concrete placement conveyor effectively mounted for universal swinging movement on the outer end of said pivot arm, a levelling cylinder operatively connected to said frame member and pendulum bracket for effecting limited angular displacement of the latter, a tie bar pivotally connected at one end to said pivot arm, a connector link pivotally connected at one end to said frame member and at its other end to the other end of the tie bar, said tie bar and connector link, together with adjacent portions of the frame member and pivot arm, constituting an articulated collapsible four-bar linkage, and an hydraulic pivot arm cylinder operatively connected to said frame member and one bar of the four-bar linkage and effective to extend and collapse the latter.

15. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 14 and wherein said hydraulic cylinder is operatively connected to the connector link.

16. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 15 and wherein the pivot arm is capable of swinging movement from a retracted position wherein it extends transversely of the vehicle chassis and lies in close proximity to said transverse frame member, throughout an angle of substantially the tie bar is effectively connected to the pivot arm at a point close to the proximate end of the latter, and the pivot arm cylinder is connected to the connector link at a point close to the proximate end of such link.

17. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 16 and wherein the fourbar linkage is substantially completely collapsible so that when the pivot arm is in its retracted position, the

tie bar, connector link, pivot arm and pivot arm cylinder assume a closely nested linear relationship in close proximity to said transverse frame member.

18. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 17 and wherein said tie bar is extensible and contractible.

19. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 18 and wherein the transverse frame member has mounted thereon a hooklike bracket within which a portion of the pivot arm rests when the latter is in its fully retracted position, thus locking the pivot arm against outward swinging movement under the influence of the pivot arm cylinder, and the levelling cylinder is effective when extended to swing the pendulum bracket throughout a degree of angular movement sufficient to raise said portion of the pivot arm clear of the hook-like bracket,

.thus releasing the pivot arm for swinging movement thereof.

20. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 19 and wherein the connector link and pivot arm cylinder are disposed in contiguity when the pivot arm is in its retracted position, and the connector link is provided with a relief area therein into which a portion of the pivot arm cylinder projects in order to enhance the nested relationship between the link and cylinder. 

1. In a ready-mix concrete-transporting vehicle, in combination, a vehicle chassis having a rear transverse frame member, a normally vertical conveyor-levelling pendulum bracket pivotally mounted on the rear end of said frame member for limited angular displacement about a horizontally and longitudinally extending axis, a pivot arm having its proximate end hingedly secured to said pendulum bracket for swinging movement about a vertical axis, a turntable mounted on the distal end of said pivot arm for rotation about a vertical axis, a carrier frame pivotally mounted on the turntable for rotation bodily therewith and for fore-andaft rocking movement about a horizontal axis, a conveyor boom slidable endwise in opposite directions through said carrier frame between projected positions on either side of the latter, an hydraulic lift cylinder operatively connected to the carrier frame and turntable for effecting rocking movements of the former, a levelling cylinder operatively connected to said frame member and pendulum bracket for effecting limited angular displacement of the latter, a tie bar pivotally connected at one end to said pivot arm, a connector link pivotally connected at one end to said frame member and at its other end to the other end of the tie bar, said tie bar and connector link, together with adjacent portions of the frame member and pivot arm, constituting an articulated collapsible four-bar linkage, and an hydraulic pivot arm cylinder operatively connected to said frame member and one bar of said four-bar linkage and effective to extend and collapse the latter.
 2. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 1 and wherein the hydraulic cylinder is operatively connected to the connector link.
 3. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 2 and wherein the pivot arm is capable of swinging movement from a retracted position wherein it extends transversely of the vehicle chassis and lies in close proximity to said transverse frame member, throughout an angle of substantially 180*, the tie bar is effectively connected to the pivot arm at a point close to the proximate end of the latter, and the pivot arm cylinder is connected to the connector link at a point close to the proximate end of such link.
 4. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 3 and wherein the four-bar linkage is substantially completely collapsible so that when the pivot arm is in its retracted position, the tie bar, connector link, pivot arm and pivot arm cylinder assume a closely nested linear relationship in proximity to said transverse frame member.
 5. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 4 and wherein the tie bar is extensible and contractible.
 6. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 4 and wherein the tie bar comprises cooperating elongated internally and externally threaded members.
 7. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 4 and including, additionally, a reversible hydraulic motor fixedly mounted on said pivot arm, and a power train operatively connecting said motor to the turntable in driving relationship.
 8. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 7 and wherein the power train comprises a chain and sprocket mechanism.
 9. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 8 and wherein the hydraulic motor is mounted on the pivot arm in close proximity to the distal end of the latter.
 10. In a ready-mix concrete-transporting vehicle, in combination, a vehicle chassis having a rear transverse frame member, a normally vertical conveyor-levelling pendulum bracket pivotally mounted on the rear end of said frame member for limited angular displacement about a horizontally and longitudinally extending axis, a pivot arm having its proximate end hingedly secured to said pendulum bracket for swinging movement about a vertical axis, a turntable mounted on the distal end of said pivot arm for rotation about a vertical axis, a carrier frame pivotally mounted on the turntable for rotation bodily therewith and for fore-and-aft rocking movement about a horizontal axis, a conveyor boom slidable endwise in opposite directions through said carrier frame between projected positions on either side of the latter, an hydraulic lift cylinder operatively connected to the carrier frame and turntable for effecting rocking movements of the former, a levelling cylinder operatively connected to said frame member and pendulum bracket for effecting limited angular displacement of the latter, a reversible hydraulic motor fixedly mounted on the pivot arm, and a power train operatively connecting said motor to the turntable in driving relationship.
 11. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 10 and wherein the power train comprises a chain and sprocket mechanism.
 12. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 10 and wherein the power train comprises an output driving sprocket on the hydraulic motor, a dual sprocket assembly mounted for rotation on the pivot arm, a driven sprocket on the turntable, a first endless chain operatively connecting said driving sprocket to a sprocket on the dual sprocket assembly, and a second endless chain operatively connecting the other sprocket on the dual sprocket assembly to the driven sprocket.
 13. In a reAdy-mix concrete-transporting vehicle, the combination set forth in claim 12 and wherein the hydraulic motor and its associated driving sprocket are mounted on the pivot arm in close proximity to the distal end of the latter.
 14. In a ready-mix concrete-transporting vehicle, in combination, a vehicle chassis having a rear transverse frame member, a normally vertical conveyor-levelling pendulum bracket pivotally mounted on the rear end of said frame member for limited angular displacement about a horizontal longitudinal axis, a pivot arm having its proximate end hingedly secured to said pendulum bracket for swinging movement about a vertical axis, a concrete placement conveyor effectively mounted for universal swinging movement on the outer end of said pivot arm, a levelling cylinder operatively connected to said frame member and pendulum bracket for effecting limited angular displacement of the latter, a tie bar pivotally connected at one end to said pivot arm, a connector link pivotally connected at one end to said frame member and at its other end to the other end of the tie bar, said tie bar and connector link, together with adjacent portions of the frame member and pivot arm, constituting an articulated collapsible four-bar linkage, and an hydraulic pivot arm cylinder operatively connected to said frame member and one bar of the four-bar linkage and effective to extend and collapse the latter.
 15. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 14 and wherein said hydraulic cylinder is operatively connected to the connector link.
 16. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 15 and wherein the pivot arm is capable of swinging movement from a retracted position wherein it extends transversely of the vehicle chassis and lies in close proximity to said transverse frame member, throughout an angle of substantially 180*, the tie bar is effectively connected to the pivot arm at a point close to the proximate end of the latter, and the pivot arm cylinder is connected to the connector link at a point close to the proximate end of such link.
 17. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 16 and wherein the four-bar linkage is substantially completely collapsible so that when the pivot arm is in its retracted position, the tie bar, connector link, pivot arm and pivot arm cylinder assume a closely nested linear relationship in close proximity to said transverse frame member.
 18. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 17 and wherein said tie bar is extensible and contractible.
 19. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 18 and wherein the transverse frame member has mounted thereon a hook-like bracket within which a portion of the pivot arm rests when the latter is in its fully retracted position, thus locking the pivot arm against outward swinging movement under the influence of the pivot arm cylinder, and the levelling cylinder is effective when extended to swing the pendulum bracket throughout a degree of angular movement sufficient to raise said portion of the pivot arm clear of the hook-like bracket, thus releasing the pivot arm for swinging movement thereof.
 20. In a ready-mix concrete-transporting vehicle, the combination set forth in claim 19 and wherein the connector link and pivot arm cylinder are disposed in contiguity when the pivot arm is in its retracted position, and the connector link is provided with a relief area therein into which a portion of the pivot arm cylinder projects in order to enhance the nested relationship between the link and cylinder. 